The present invention relates to a self-shining aerosol-type shoe polish composition, which comprises a liquefied gas as a solvent as well as a propellant gas without auxiliary solvent conventionally used.
Aerosol-type polishes have been extensively used for polishing shoes, automobiles, household care, etc. Conventionally, an aerosol is prepared by injecting a stock solution and a liquefied propellant gas, which serves to spray the stock solution with a suitable pressure, into a container under a predetermined pressure.
Stock solution is generally prepared by dissolving an effective component in a solvent such as petroleum fraction, alcohol, water and synthetic solvent. The content of such stock solution in an aerosol-type polish composition is normally 55 to 70% by volume based on the total polish composition.
On the other hand, the propellant gas may be LPG (liquefied petroleum gas), DME (dimethylether), Freon or carbon dioxide gas. CO2 gas is not liquefied at room temperature but may dissolve in a specific solvent to a high degree, and therefore, can play a role in blasting aerosol when sprayed. The propellant gas should be selected in consideration of the miscibility with the stock solution to optimize the effectiveness of spraying, liquefying pressure, cost, etc.
Conventional aerosol-type polish compositions for automobile and household care products are prepared by mixing LPG as a propellant gas and a stock solution comprising a silicone compound as an effective component, and a solvent selected from the group consisting of dearomatized kerocene, naphtha and alcohol; or by mixing DME as a propellant gas with a silicone emulsion diluted to 1 to 50% by volume with water or alcohol as a stock solution. Such aerosol compositions consist of 50 to 70% by volume of the stock solution and the remainder of liquefied propellant gas.
However, when the above conventional aerosol-type polish composition is used for polishing shoes, it needs a long drying time as well as an additional polishing step using dry cloth.
Accordingly, it is a primary object of the present invention to provide an aerosol-type shoe polish composition having a reduced drying time and improved self-shining characteristics.
The above object of the invention can be accomplished by providing a self-shining aerosol-type shoe polish composition consisting essentially of 0.5 to 25% by volume of a silicone compound, optionally 3 to 25% by volume of a drying retardant and/or 0.1 to 1% by volume of an anti-static agent component, and the remainder of liquefied gas which also functions as a solvent as well as a propellant gas, whereby the aerosol composition is dispersed finely when sprayed, and applied uniformly to the surface of shoes.
The self-shining aerosol-type shoe polish composition in accordance with the present invention comprises a silicone compound as an effective component, a drying retardant and liquefied gas without any other solvent.
In the self-shining aerosol-type shoe polish composition in accordance with the present invention, a silicone compound is employed as an effective component. Preferably, silicone compounds which may be used in the present invention include a silicone oil, a water-soluble silicone oil, a modified silicone oil, a silicone wax, a silicone resin and a mixture thereof. As a liquefied gas component in the composition, LPG, DME or a mixture thereof is preferred; and as a drying retardant, pentane, hexane, a silicone oil having the boiling point in the range of 60 to 150xc2x0 and the surface tension in the range of 15 to 25 dyne/cm, and a mixture thereof may be used.
When the conventional aerosol-type polish composition is sprayed, the polishing component is applied on the surface of shoes uniformly and shines the shoes with vaporization of the liquefied propellant gas component. Since the liquefied propellant gas has a tendency to vaporize instantaneously when sprayed into atmosphere, the effective component droplet becomes chilled and thickened very fast, which makes the shining layer formed on the surface of shoes be withdrawn minutely, whereby the polishing effect of the polish component may become worse and the surface of the shoes gets uneven. In order to solve the above-mentioned problems, the self-shining aerosol-type shoe polish composition in accordance with the present invention further comprises a drying retardant. As a drying retardant, hexane is preferred since its boiling point and surface tension are in the range of 65 to 70xc2x0 and in the range of 17 to 19 dyne/cm, respectively. Compared with pure water having the surface tension of 73 dyne/cm or a surfactant added water having the surface tension of 35 to 40 dyne/cm, hexane shows excellent wetting and leveling effects. The low surface tension of hexane makes it possible to produce thin and uniform layer formation, thereby increasing the polishing effect. Also, the moderate heat of vaporization and the suitable vaporizing rate of hexane prevent the effective component from excessively rapidly cooling and thickening due to instantaneous vaporization of the liquefied propellant gas.
In order to prevent the aggregation of dust on the shoe surface, the aerosol-type shoe polish composition in accordance with the present invention may further comprise 0.1 to 1% by volume of an anti-static agent component, for example, a positively-charged silicone compound such as polyether functionalized silicones (PFS), since the dust in the air has a positive charge.
In a preferred embodiment, the content of silicone compound in the polish composition of the present invention is in the range of 0.5 to 25% by volume based on the total polish composition. If the content of silicone compound is less than 0.5% by volume, the polishing and water repellent effect may not be satisfactory, while if it is higher than 25% by volume, the polishing layer formed on the surface becomes excessively thick, giving rise to scattered reflection and drying problem.
Preferably, the content of drying retardant component is in the range of 3 to 25% by volume based on the total aerosol-type polish composition. If the content of drying retardant is less than 3% by volume, the retarding effect may be insufficient, while if it is higher than 25% by volume, the silicone oil layer may be contaminated due to excessive retardation of drying.